Field of the Invention
The present invention relates generally to medical systems for use in the treatment of injuries, and, in particular, relates to a device for treating joint injuries, and, in great particularity, relates to a device for resetting a joint dislocation, and in greater particularity, relates to an electro-mechanical means for controlling the treatment to minimize pain and the use of anesthesia.
Description of the Prior Art
With people being more active in sports today such as soccer, football, basketball, hockey, etc., more and more people are receiving shoulder injuries, and in particular, dislocations of the shoulder wherein the humerus head of the arm is pulled away from the tablet of the fossa glenoidalis joint surface. This is a painful injury.
Resetting of the shoulder is primarily addressed by peculiar manipulations or pulling of the upper arm in various directions as has been done in the past. It is a well known fact that moving the dislocated joint is painful so most methods are not even attempted without administering pain reduction drugs. In the pulling method, the pulling is typically done by human strength—in various directions—or with a weight, acting mostly downward according to the law of gravity.
An example of the latter method for relocating shoulder dislocations is the so-called Stimson technique, during which the injured arm of the patient, who is lying on his/her abdomen, is pulled down perpendicular to the body with the use of weights. This method is disclosed in U.S. Pat. No. 5,997,494, according to which a quantity of fixed weights depending on the patient's physical condition and the state of the dislocation (advantageously with a mass of 4.5-12 kg) is placed in a weight container connected to a cuff attached to the lower arm of the patient. Alternatively, water may be added to a container in an increasing amount; in this manner, a smooth extension can be achieved.
Another prior art example for treating the shoulder dislocation is disclosed in U.S. Pat. No. 4,616,637, according to which the arm of the injured person, who is lying on his/her side, is pulled upward by attaching to the hand a rope passing through an overhead pulley.
The essence of the above examples is thus that the limb of the injured person is pulled with weights thereby extending the muscles whose contraction must be overcome during the relocation of the dislocation. Their disadvantage is the length of the traction pull and the solutions used to exert force can cause pain because of possible displacements of the arm; therefore drugs (sedatives, local anesthesia, muscle relaxants) are generally needed. Administering drugs, however, can always be associated with side effects, including serious complications.
Only a few methods may work without drug administration. One of these is the Arlt method, where the relocation always takes place without giving drugs! (Arlt: “Erfahrungen bei Einrichtung der Schulterverrenkungen” [Experiences in Relocating Shoulder Dislocations], Der Chirurg. 1941, vol. 13, page 416 2). This method has been practiced in a sparing manner and mostly painless. Its essence is that for every dislocation, there is one position that is “practically” pain free. This is generally the position where the patient holds the dislocated arm with the good arm.
Sometimes, however, the task of the physician is to find this pain-free position by fine movements of the shoulder. Maintaining this position, the patient is made to sit so that his shoulder girdle is supported in the underarm by a back support of a chair, then, while maintaining this position, the arm is pulled downward in a sparing manner and gradually until the dislocated humerus head jumps back into the glenoid cavity. A chair having this adjustable underarm support has been specifically designed for this procedure: (manufacturer: Dr. Franz Merska, Vienna, Austria, product name: “REPOSITIONSSTUHL” [REPOSITION CHAIR]”).
The above methods may present one or more disadvantages to the patient. For example, the position of the arm changes during pulling by manual force thus causing pain. It also has the disadvantage that the extent and strength of the pulling force cannot be measured exactly in relation to the extension of the arm; one of the main reasons for failure, however, is that the physician gets tired and gives up.
Accordingly, there is an established need for a device that prevents the above mentioned uncertainties and can be applied in a controlled manner without the use of drugs for resetting a dislocated shoulder.